The Representation Commission has recommended the number of general electorates in Auckland be increased from 23 to 24.
The Commission meets every five years to look at the boundaries of electorates, based on census data. This round sets the boundaries for the 2014 and 2017 elections.
The new Auckland electorate will be called Upper Harbour and draws voters from the electorates of East Coast Bays and Helensville in the north and Te Atatu in the south.
Another electorate, Kelston, has also been created and will effectively replace the existing seat of Waitakere, at present held by Social Development Minister Paula Bennett.
Just 13 North Island electorates will retain their current boundaries.
In Christchurch there are also significant boundary changes, with Christchurch East drawing populations from Christchurch Central, and Bromley from Port Hills.
The boundaries of the seven Maori electorates will remain the same.